Complex 99mTc-PDA-DTPA for myocardial imaging

The 123I-labeled fatty acids such as 123I-Iodophenylpentadecanoic acid and 123I-Beta-methyliodophenylpentadecanoic acid are the agents used clinically for myocardial imaging. Fatty acids are the major source of energy for the normal myocardium. However, under ischemic conditions the myocardial cells switch to glucose metabolism for their energy needs. Fatty acids undergo prolonged metabolic stunning in patients with reversible ischemia, thereby helping in early diagnosis of coronary artery disease in highrisk patients. High cost andlimited availability of cyclotron-produced 123I, makes 99mTc-labeled fatty acids more desirable for the purpose. In diagnosis the dominant radionuclide is 99mTc. It is estimated that it is involved in about 85% of all imaging procedures in nuclear medicine. The method for preparation of new 99mTc-fatty chemical systems based on modified diethylene triamine pentaacetic acid (DTPA) molecule has been elaborated in this work . The main advantage using DTPA as chelate agent for radioactive label, is the molecule or it's derivative ability to form sufficiently stable complexes with different radioactive metals including technetium-99. Moiety of pentadecanoic acid addition gave the ability to prepare modified complex of DTPA. In a labeling procedure, freshly eluted Na99mTcO4 (20mCi) was added to a mixture of cysteine, stannous chloride, PDK-DTPA and ethanol in a vial. On keeping the reaction mixture at 90 0C for 30 min, [99mTc-PDK-DTPA] radiopharmaceutical was formed. Thereafter, the reaction mixture was cooled over ice and characterized by HPLC. The result of dynamic scintigraphic research showed, that after being injected, the substance is actively acumulated into myocardium. Eventually one can say that modified DTPA-moleculs are functionally suitable for myocardial imaging

РАСЧЕТ МОРФОМЕТРИЧЕСКИХ ХАРАКТЕРИСТИК ПРОРАНА И МАКСИМАЛЬНЫХ РАСХОДОВ ПРИ ПРОРЫВАХ ГРУНТОВЫХ ПЛОТИН

The work is devoted to the calculation of the size of the closure channel in the ground dams when water is poured from the water reservoir through peak and the extreme discharge of the dam break wave. The authors analyzed the methods of calculation prescribed in regulations and recommended by regulatory authorities. The calculation was made of the morphometric characteristics of the closure channel and extreme discharge of the dam break wave by various methods for specific objects, the comparison with expert estimates of these parameters. It is noted that the method, described in two regulations, has no physical justification, because according to it the size of closure channel and the parameters of breakthrough wave do not depend on the initial volume of water in the reservoir. The calculation method in the third regulation, does not take into account such factor as the time of erosion and the results are different at times with different specified step of erosion depth. This regulation is characterized by the use of empirical relations, which have a rather narrow range of use, and a lack of account of the relationship between the formation of the closure channel and the value of water discharge. Due to the lack of validity of the recommended calculation methods and large variation with expert estimates prescribed in the regulations, there is a need to create new alternative methods of calculation. This article discusses 2 such methods developed in various organizations. The first of them indirectly takes into account the material of the dam through calculated non-eroding velocity. The second one is based on the physical process of erosion, that is distinguishe it from others. As a test of the calculated values, there were used data on several recent catastrophic breakthroughs of groundwater dams. The comparison results allow us to conclude that alternative methods give greater accuracy. Based on the previous, can be done a preliminary conclusion about the need to revise existing regulations.Работа посвящена вопросу расчета размеров прорана в грунтовых плотинах при переливе воды из водохранилища через гребень и максимального расхода волны прорыва. Были проанализированы методы расчета, прописанные в нормативных документах и рекомендованные контролирующими органами. Выполнен расчет морфометрических характеристик прорана и максимальных расходов прорывной волны различными методами для конкретных объектов, сравнение с экспертными оценками этих параметров. Отмечено, что изложенная в двух нормативных документах методика, не имеет под собой физического обоснования, поскольку полученные размеры прорана и параметры волны прорыва не зависят от первоначального объема воды в водохранилище. В свою очередь расчетная схема другого нормативного документа не учитывает такой фактор, как время размыва и результат расчета отличается в разы при различном заданном шаге глубины размыва. Для данного документа характерно использование эмпирических соотношений, которые имеют довольно узкий диапазон использования, а также недоучет связи между формированием прорана и величиной сброса воды. Из-за недостаточной обоснованности рекомендованных методик и больших несоответствий с экспертными оценками возникает необходимость создания новых альтернативных методов расчета. В данной статье рассмотрено 2 таких метода, разработанных в различных организациях. Первый метод косвенно учитывает материал плотины через расчет неразмывающей скорости. В основе второго метода лежит физический процесс размыва, что выгодно отличает его от других. В качестве проверки расчетных значений были использованы данные о нескольких произошедших в последнее время катастрофических прорывах грунтовых плотин. Результаты сравнения позволяют сделать вывод о том, что альтернативные методы дают большую точность. На основе вышесказанного можно сделать предварительный вывод о необходимости пересмотра существующих нормативных документов.   Литература Бобков С.Ф., Боярский В.М., Векслер А.Б., Швайнштейн A.M. Основные факторы учета пропускной способности гидроузлов при декларировании их безопасности // Гидротехническое строительство. 1999. №4. С. 2-9. Кадацкая М.М., Виноградов А.Ю., Кацадзе В.А., Беленький Ю.И., Бачериков И.В., Хвалев С.В., Каляшов В.А. Анализ методов расчета неразмывающей скорости при проектировании водопропускных и водоотводных сооружений лесного хозяйства // Известия Санкт-Петербургской лесотехнической академии. 2019. Вып. 227. С. 174-187. DOI: 10.21266/2079-4304.2019.227.174-187 Катастрофы конца XX века / Под ред. В.В. Владимирова. М.: Издательство Геополитика, 2001. 400 с. Малик Л.К. Чрезвычайные ситуации, связанные с гидротехническим строительством ретроспективный обзор // Гидротехническое строительство. 2009. №12. C. 2-16 Пономарчук К.Р. Оценка параметров развития прорана при разрушении грунтовой плотины // Природообустройство. 2011. №3. С. 77-82. Чугаев Р.Р. Гидравлика: учебник для вузов. Л.: Энергоиздат, 1982. 672 с. Фролов Д.И., Волосухин В.А. Совершенствование российского законодательства по безопасности гидротехнических сооружений // Бюллетень «Использование и охрана природных ресурсов в России». 2012. №6. С. 17-2

Use of autoleukocyte, labelled with 99mTc-exametazine for evaluation of inglammatory changes in myocardium

Our purpose was to study the possibilities of autoleukocyte, labelled in vitro with 99mTc-exametazine (99m Tc-HMPAO), in evaluation of inflammatory changes of myocardium at patients with persistent form of atrial fibrillation (AF).We examined 30 patients with idiopathic persistent form of AF. For identification of the inflammatory areas in a myocardium before ablation scintigraphy (SPECT) 99mTc-HMPAO – leucocytes was carried out. Upon completion of scanning a perfusion scintigraphy of a myocardium with a 99mTc-methoxyisobutyl isonitrile (99mTc-MIBI) («Tehnetril» 99mTc, JSC Diamed, Russia) in rest under the standard protocol was carried out. Pathologic accumulation of 99mTc-HMPAO-leukocytes in a myocardium was revealed at 6 (20%) of the examined patients. Sensitivity of SPECT with 99mTc-HMPAO-leukocytes in diagnostics of inflammatory changes of a myocardium, according to our data, was - 80%, specificity - 92%, diagnostic accuracy - 90%

Use of autoleukocyte, labelled with 99mTc-exametazine for evaluation of inglammatory changes in myocardium

Our purpose was to study the possibilities of autoleukocyte, labelled in vitro with 99mTc-exametazine (99m Tc-HMPAO), in evaluation of inflammatory changes of myocardium at patients with persistent form of atrial fibrillation (AF).We examined 30 patients with idiopathic persistent form of AF. For identification of the inflammatory areas in a myocardium before ablation scintigraphy (SPECT) 99mTc-HMPAO – leucocytes was carried out. Upon completion of scanning a perfusion scintigraphy of a myocardium with a 99mTc-methoxyisobutyl isonitrile (99mTc-MIBI) («Tehnetril» 99mTc, JSC Diamed, Russia) in rest under the standard protocol was carried out. Pathologic accumulation of 99mTc-HMPAO-leukocytes in a myocardium was revealed at 6 (20%) of the examined patients. Sensitivity of SPECT with 99mTc-HMPAO-leukocytes in diagnostics of inflammatory changes of a myocardium, according to our data, was - 80%, specificity - 92%, diagnostic accuracy - 90%

Validation of the Finnish diabetes risk score (FINDRISC) for the Caucasian population of Siberia

Aim. A validation of the Finnish diabetes risk score (FINDRISC) was conducted among the Siberian population. FINDRISC was used to study the prevalence of risk factors for type 2 diabetes mellitus (T2DM) and to estimate the incidence of T2DM in high-risk groups during a 10-year observation period.  Materials and methods. A total of 9,360 subjects aged between 45 and 69 years were enrolled in this cross-sectional, population-based study. FINDRISC was used to group 8,050 people without diabetes according to their risk for T2DM. Statistical analysis was performed using SPSS.  Results. When a cutoff point of 11 was used to identify those with diabetes, sensitivity was 76. 0% and specificity was 60. 2%. The area under the receiver operating curve for diabetes was 0. 73 (0. 73 for men and 0. 70 for women). More than one-third (31. 7%) of the adult population of Novosibirsk was estimated to have medium, high or very high risk of developing T2DM in the next 10 years. Cases of T2DM estimated to occur during the 10 years of follow-up had significantly higher incidence of risk factors such as BMI ≥30 kg/m2, waist circumference 102 cm in men and 88 cm in women and a family history of T2DM and were more likely to take drugs to lower blood pressure.  Conclusion. FINDRISC provided good results in our sample, and we recommend its use in the Siberian population

Isolated Atrial Fibrillation, Inflammation and Efficacy of Radiofrequency Ablation: Preliminary Insights Based on a Single-Center Endomyocardial Biopsy Study

The aim of the study was to evaluate the inflammatory changes in the myocardium, based on endomyocardial biopsy (EMB) data in patients undergoing radiofrequency ablation (RFA) for idiopathic atrial fibrillation (AF). A total of 67 patients with idiopathic AF were enrolled in the study. Patients underwent the intracardiac examination, RFA of AF, and EMB with histological and immunohistochemical studies. The catheter-treatment effectiveness, and occurrence of early and late recurrences of atrial tachyarrhythmias, were assessed depending on the identified histological changes. Nine patients (13.4%) did not have any histological changes in the myocardium according to EMB. Fibrotic changes were detected in 26 cases (38.8%). Inflammatory changes according to the Dallas criteria were observed in 32 patients (47.8%). The follow-up period for patients averaged 19.3 ± 3.7 months. The effectiveness rates of primary RFA were 88.9% in patients with the intact myocardium, 46.2% in patients with fibrotic changes of varying severity, and 34.4% in patients with the presence of criteria for myocarditis. No early recurrence of arrhythmias was observed in patients with unchanged myocardia. The presence of inflammatory and fibrotic changes in the myocardium increased the rates of early and late arrhythmia recurrences and accordingly halved the effectiveness RFA of AF

Isolated Atrial Fibrillation, Inflammation and Efficacy of Radiofrequency Ablation: Preliminary Insights Based on a Single-Center Endomyocardial Biopsy Study

The aim of the study was to evaluate the inflammatory changes in the myocardium, based on endomyocardial biopsy (EMB) data in patients undergoing radiofrequency ablation (RFA) for idiopathic atrial fibrillation (AF). A total of 67 patients with idiopathic AF were enrolled in the study. Patients underwent the intracardiac examination, RFA of AF, and EMB with histological and immunohistochemical studies. The catheter-treatment effectiveness, and occurrence of early and late recurrences of atrial tachyarrhythmias, were assessed depending on the identified histological changes. Nine patients (13.4%) did not have any histological changes in the myocardium according to EMB. Fibrotic changes were detected in 26 cases (38.8%). Inflammatory changes according to the Dallas criteria were observed in 32 patients (47.8%). The follow-up period for patients averaged 19.3 ± 3.7 months. The effectiveness rates of primary RFA were 88.9% in patients with the intact myocardium, 46.2% in patients with fibrotic changes of varying severity, and 34.4% in patients with the presence of criteria for myocarditis. No early recurrence of arrhythmias was observed in patients with unchanged myocardia. The presence of inflammatory and fibrotic changes in the myocardium increased the rates of early and late arrhythmia recurrences and accordingly halved the effectiveness RFA of AF

Complex 99mTc-PDA-DTPA for myocardial imaging

The 123I-labeled fatty acids such as 123I-Iodophenylpentadecanoic acid and 123I-Beta-methyliodophenylpentadecanoic acid are the agents used clinically for myocardial imaging. Fatty acids are the major source of energy for the normal myocardium. However, under ischemic conditions the myocardial cells switch to glucose metabolism for their energy needs. Fatty acids undergo prolonged metabolic stunning in patients with reversible ischemia, thereby helping in early diagnosis of coronary artery disease in highrisk patients. High cost andlimited availability of cyclotron-produced 123I, makes 99mTc-labeled fatty acids more desirable for the purpose. In diagnosis the dominant radionuclide is 99mTc. It is estimated that it is involved in about 85% of all imaging procedures in nuclear medicine. The method for preparation of new 99mTc-fatty chemical systems based on modified diethylene triamine pentaacetic acid (DTPA) molecule has been elaborated in this work . The main advantage using DTPA as chelate agent for radioactive label, is the molecule or it's derivative ability to form sufficiently stable complexes with different radioactive metals including technetium-99. Moiety of pentadecanoic acid addition gave the ability to prepare modified complex of DTPA. In a labeling procedure, freshly eluted Na99mTcO4 (20mCi) was added to a mixture of cysteine, stannous chloride, PDK-DTPA and ethanol in a vial. On keeping the reaction mixture at 90 0C for 30 min, [99mTc-PDK-DTPA] radiopharmaceutical was formed. Thereafter, the reaction mixture was cooled over ice and characterized by HPLC. The result of dynamic scintigraphic research showed, that after being injected, the substance is actively acumulated into myocardium. Eventually one can say that modified DTPA-moleculs are functionally suitable for myocardial imaging

The Risk of Type 2 Diabetes Mellitus in a Russian Population Cohort According to Data from the HAPIEE Project

The aim of this study is to investigate the 14-year risk of type 2 diabetes mellitus (T2DM) and develop a risk score for T2DM in the Siberian cohort. A random population sample (males/females, 45–69 years old) was examined at baseline in 2003–2005 (Health, Alcohol, and Psychosocial Factors in Eastern Europe (HAPIEE) project, n = 9360, Novosibirsk) and re-examined in 2006–2008 and 2015–2017. After excluding those with baseline T2DM, the final analysis included 7739 participants. The risk of incident T2DM during a 14-year follow-up was analysed using Cox regression. In age-adjusted models, male and female hazard ratios (HR) of incident T2DM were 5.02 (95% CI 3.62; 6.96) and 5.13 (95% CI 3.56; 7.37) for BMI ≥ 25 kg/m2; 4.38 (3.37; 5.69) and 4.70 (0.27; 6.75) for abdominal obesity (AO); 3.31 (2.65; 4.14) and 3.61 (3.06; 4.27) for fasting hyperglycaemia (FHG); 2.34 (1.58; 3.49) and 3.27 (2.50; 4.26) for high triglyceride (TG); 2.25 (1.74; 2.91) and 2.82 (2.27; 3.49) for hypertension (HT); and 1.57 (1.14; 2.16) and 1.69 (1.38; 2.07) for family history of diabetes mellitus (DM). In addition, secondary education, low physical activity (PA), and history of cardiovascular disease (CVD) were also significantly associated with T2DM in females. A simple T2DM risk calculator was generated based on non-laboratory parameters. A scale with the best quality included waist circumference >95 cm, HT history, and family history of T2DM (area under the curve (AUC) = 0.71). The proposed 10-year risk score of T2DM represents a simple, non-invasive, and reliable tool for identifying individuals at a high risk of future T2DM